The DOT said the latest project is yet another diverging diamond configuration, and it'll make traffic safer and more efficient.

"Most people who drive that route know there's a capacity problem at the interchange northbound exit ramp," said Tony Gustafson, assistant District 1 engineer at Iowa DOT. "It'll back up almost to the interstate."

Plans call for expanding four miles of I-35 at Ankeny exits Oralabor, First Street and Northwest 36th Street.

"There's always a concern with traffic backing up on a ramp on to the main line. You know, folks don't accept the possibility of cars stopped," Gustafson said.

Construction is slated from 2018 to 2020.

The project will cost $55 million and is funded by federal and state road use tax.

Gustafson said it'll be similar to the diverging diamond interchange that opened Tuesday on I-80 and the new Grand Prairie Parkway.

"It's designed to handle traffic 2040 and beyond, so the new design will alleviate any backup concerns at this location," he said. "They've been built in other states, and they've shown to handle traffic well."

A public hearing is planned for Dec. 15 from 5 p.m. to 6:30 p.m. at the Best Western Metro North in Ankeny.